Pages

Thursday, April 29, 2010

When two leaks were first reported in the damaged oil wellhead, reports estimated that the leaks were discharging about 1,000 barrels (42,000 gallons) of oil per day. That figure has been quoted consistently since then. Apparently the wellhead has a third leak, so the leakage is actually much greater: about 5,000 barrels (210,000 gallons) per day.

The inability of the Coast Guard and BP to shut off the leaks makes it more likely the oil slick will hit the coast when the winds shift.

Meanwhile, an air of inevitability has settled in — a sense that the question about the oil reaching marshes and beaches is no longer if, but when. Experts from the National Oceanic and Atmospheric Administration said the oil is likely to hit Louisiana on Friday night.

Gulf winds have pushed the slick farther from Florida's coastline, said Mike Sole, secretary of the Florida Department of Environmental Protection. On Tuesday it was 89 miles from Pensacola, and by Wednesday it was 127 miles. But that's no reason to celebrate, he said.

"If the winds shift again, Florida could easily be the target," Sole said.

But some parts of the swampy coastline will be impossible to protect, said NOAA ecologist Tom Minello. Once it hits those mangroves, he said, "it'll just kill all the vegetation. It's years before it will recover. The stuff's pretty toxic, and it will kill all the growth that supports the shrimp and crabs," hurting a seafood industry that's still recovering from Hurricane Katrina.

While noting he wouldn't want oil to hit any of Florida's coast, Sole said it would be easier cleaning it off of a beach than scrubbing sensitive estuaries. The only way to get oil out of a contaminated marsh, he said, "is to burn the marsh."

Audubon has a good listing of which bird species might be at risk from an oil slick in Louisiana. Most of them are waterbirds that use coastal wetlands for nesting, but migrating birds are at risk as well.

On Wednesday, two vessels dispatched by the Coast Guard and the British oil company BP - which had hired the sunken rig - swept the thickest concentrations of oil on the surface into a 500ft (150m) fire-resistant boom.

They then towed it to a five-mile "burn zone" set up inside the slick, where it was set alight shortly before nightfall. It will be allowed to burn for an hour.

If the test is deemed successful, BP is expected to continue the controlled burns as long as the weather conditions are favourable.

The decision to start the test burn came after the US National Oceanic and Atmospheric Administration (NOAA) warned that winds in the area were about to shift and possibly push the oil onto the coast by Friday night.